Secondary Accidents Research Articles

Estimation of lateral offset and drift angle for application in secondary collision avoidance system

Recent reports show that the secondary collision on the road gives much higher fatality rate than the other traffic accidents. Many studies have been carried out to prevent the secondary accidents and as a result automotive companies began to introduce brake-based secondary collision avoidance systems. To prevent the secondary accidents it is important to monitor and control the lateral deviation of the vehicle after the primary collision. An estimator for the vehicle’s lateral offset and drift angle based on the in-vehicle sensors and the camera was developed in this paper. By employing sensor fusion scheme and applying extended Kalman filter, the estimator has been designed so that it works even when the camera loses the image of the lanes due to sudden change of the vehicle’s heading angle. For validation of the estimator, simulation has been carried out on various collision scenarios. The simulation results indicated that the estimator of this paper could calculate the vehicle’s lateral deviation with robustness that may be required for application in the secondary collision avoidance systems.

통합영상정보 생성을 활용한 교차로 영상기록장치 시스템 구현에 관한 연구

본 논문은 교차로 영상기록장치 시스템으로서 교차로 구간 영상과 신호등 현시 영상을 수집하여 하나의 영상정보로 통합한 후 중앙센터로 전송하는 시스템이다. 시스템은 교차로 영상과 신호등 현시 영상을 획득하는 영상 획득 과정과 획득한 두 영상을 단일의 영상으로 통합하는 과정을 거쳐 중앙센터로 전송하고 기록하도록 구성되어 있다. 이 시스템을 활용하여 사고 발생시 유고정보를 신속히 전파하여 2차 사고를 예방하고 사고의 원인을 판단하는데 소요되는 시간과 분쟁을 줄일 수 있을 것으로 기대된다. This paper is Intersection image recording system for transmitting to the central center after integrating the intersection image and signal split image into one image information. The system was configured to collect the intersection image and the signal split image and transmitted to the central center after integrating images into one image and recorded. The system is expected to be effective in preventing a secondary accident by immediately propagate the accident information and reduce the time it takes to dispute and determine the cause of the accident.

Detecting and positioning of traffic incidents via video‐based analysis of traffic states in a road segment

Non-recurrent traffic incidents (accidents, stalled vehicles and spilled loads) often bring about traffic congestion and even secondary accidents. Detecting and positioning them quickly and accurately has important significance for early warning, timely incident-disposal and speedy congestion-evacuation. This study proposes a video-based detecting and positioning method by analysing distribution characteristics of traffic states in a road segment. Each lane in the monitored segment is divided into a cluster of cells. Traffic parameters in each cell, including flow rate, average travel speed and average space occupancy, are obtained by detecting and tracking traffic objects (vehicles and spilled loads). On the basis of the parameters, traffic states in the cells are judged via a fuzzy-identification method. For each congested cell, a feature vector is constructed by taking its state together with states of its upstream and downstream neighbouring cells in the same lane. Then, a support vector machine classifier is trained to detect incident point. If a cell is judged to be corresponding to an incident point at least for two successive time periods, an incident is detected and its position is calculated based on the identity number of the cell. Experiments prove the efficiency and practicability of the proposed method.

Experimental and modeling study of the behavior of a large-scale spill fire on a water layer

Spill fires pose a great threat to surrounding facilities and easily trigger secondary accidents in industrial parks. However, few studies have been conducted to build a spill fire burning rate model. In this paper, the behavior of large-scale n-Heptane spill fires on water, including the spread rate, quasi-steady burning areas and burning rate, has been experimentally studied for continuous discharge situations. The experiment was carried out in a rectangular concrete trench (12 m × 1 m) with heptane discharge rates ranging from 10 L/min to 60 L/min. The results show that in the case where there is no ignition, the spread rate is approximately linear to the discharge rate. In addition, the relation between the spread velocity and the discharge rate on rectangular water surface was obtained. Under ignition conditions, the quasi-steady burning areas are proportional to the discharge rates. Moreover, the burning rate of spill fires is approximately 0.57 times smaller than that of pool fires at the same burning diameter. This burning rate decrease phenomenon is mainly due to the transmitted thermal radiation through the heptane layer and to the heat conduction from the heptane layer to the water. Based on the pool fires’ burning rate model, we then developed a modified model for heptane spill fires by calculating the heat loss of fuel layer. This modified model can predict the spill fire burning rate, and provides a sound basis for calculating the burning areas of spill fires.

Identification of freeway secondary accidents with traffic shock wave detected by loop detectors

Secondary traffic accidents are generally recorded without being specifically noted as such in the accident database, leading to difficulty in the study of such accidents. Previous research generally classified secondary incidents by predefining fixed spatio-temporal boundaries—a method that can be very subjective. Using 10,762 accident records gathered from 2012 upstream loop detector data on a California interstate freeway, this paper proposes a dynamic method for more convincing and accurate classification based on traffic shock waves detected by the loop detectors. This method identifies and associates a secondary accident with its primary accident if it is tested and found to have occurred within the spatio-temporal impact area of the primary accident. Shock waves from each accident are calculated and updated along freeway via multiple detectors, and secondary accidents are identified as those that occur within the spatio-temporal boundaries of a primary accident. Results show that secondary accidents account for 1.08% of California interstate freeway accidents, which is much lower than previous research estimates. Dispersed spatio-temporal gaps between primary and secondary accident pairs were found with an expectation of 71.09min and 3.88miles with a standard deviation of 55.36min and 4.64miles respectively.

A combined M5P tree and hazard-based duration model for predicting urban freeway traffic accident durations

The duration of freeway traffic accidents duration is an important factor, which affects traffic congestion, environmental pollution, and secondary accidents. Among previous studies, the M5P algorithm has been shown to be an effective tool for predicting incident duration. M5P builds a tree-based model, like the traditional classification and regression tree (CART) method, but with multiple linear regression models as its leaves. The problem with M5P for accident duration prediction, however, is that whereas linear regression assumes that the conditional distribution of accident durations is normally distributed, the distribution for a “time-to-an-event” is almost certainly nonsymmetrical. A hazard-based duration model (HBDM) is a better choice for this kind of a “time-to-event” modeling scenario, and given this, HBDMs have been previously applied to analyze and predict traffic accidents duration. Previous research, however, has not yet applied HBDMs for accident duration prediction, in association with clustering or classification of the dataset to minimize data heterogeneity. The current paper proposes a novel approach for accident duration prediction, which improves on the original M5P tree algorithm through the construction of a M5P-HBDM model, in which the leaves of the M5P tree model are HBDMs instead of linear regression models. Such a model offers the advantage of minimizing data heterogeneity through dataset classification, and avoids the need for the incorrect assumption of normality for traffic accident durations. The proposed model was then tested on two freeway accident datasets. For each dataset, the first 500 records were used to train the following three models: (1) an M5P tree; (2) a HBDM; and (3) the proposed M5P-HBDM, and the remainder of data were used for testing. The results show that the proposed M5P-HBDM managed to identify more significant and meaningful variables than either M5P or HBDMs. Moreover, the M5P-HBDM had the lowest overall mean absolute percentage error (MAPE).

Modeling secondary accidents identified by traffic shock waves

The high potential for occurrence and the negative consequences of secondary accidents make them an issue of great concern affecting freeway safety. Using accident records from a three-year period together with California interstate freeway loop data, a dynamic method for more accurate classification based on the traffic shock wave detecting method was used to identify secondary accidents. Spatio-temporal gaps between the primary and secondary accident were proven be fit via a mixture of Weibull and normal distribution. A logistic regression model was developed to investigate major factors contributing to secondary accident occurrence. Traffic shock wave speed and volume at the occurrence of a primary accident were explicitly considered in the model, as a secondary accident is defined as an accident that occurs within the spatio-temporal impact scope of the primary accident. Results show that the shock waves originating in the wake of a primary accident have a more significant impact on the likelihood of a secondary accident occurrence than the effects of traffic volume. Primary accidents with long durations can significantly increase the possibility of secondary accidents. Unsafe speed and weather are other factors contributing to secondary crash occurrence. It is strongly suggested that when police or rescue personnel arrive at the scene of an accident, they should not suddenly block, decrease, or unblock the traffic flow, but instead endeavor to control traffic in a smooth and controlled manner. Also it is important to reduce accident processing time to reduce the risk of secondary accident.

Application of dynamic Bayesian network to risk analysis of domino effects in chemical infrastructures

A domino effect is a low frequency high consequence chain of accidents where a primary accident (usually fire and explosion) in a unit triggers secondary accidents in adjacent units. High complexity and growing interdependencies of chemical infrastructures make them increasingly vulnerable to domino effects. Domino effects can be considered as time dependent processes. Thus, not only the identification of involved units but also their temporal entailment in the chain of accidents matter. More importantly, in the case of domino-induced fires which can generally last much longer compared to explosions, foreseeing the temporal evolution of domino effects and, in particular, predicting the most probable sequence of accidents (or involved units) in a domino effect can be of significance in the allocation of preventive and protective safety measures. Although many attempts have been made to identify the spatial evolution of domino effects, the temporal evolution of such accidents has been overlooked. We have proposed a methodology based on dynamic Bayesian network to model both the spatial and temporal evolutions of domino effects and also to quantify the most probable sequence of accidents in a potential domino effect. The application of the developed methodology has been demonstrated via a hypothetical fuel storage plant.

Competing risks mixture model for traffic incident duration prediction

Traffic incident duration is known to result from a combination of multiple factors, including covariates such as spatial and temporal characteristics, traffic conditions, and existence of secondary accidents but also the clearance method itself. In this paper, a competing risks mixture model is used to investigate the influence of clearance methods and various covariates on the duration of traffic incidents and predict traffic incident duration. The proposed mixture model considers the uncertainty in any of five clearance methods that occurred. The probability of the clearance method is specified in the mixture by using a multinomial logistic model. Three candidate distributions, namely, generalized gamma, Weibull, and log-logistic are tested to determine the most appropriate probability density function of the parametric survival analysis model. The unobserved heterogeneity is also incorporated into the mixture model in a way that allows parameters to vary across observations based on the three candidate distributions. The methods are illustrated with incident data from Singaporean expressways from January 2010 to December 2011. Regression analysis reveals that the probability of different clearance methods and the duration of traffic incidents are both significantly affected by various factors, such as traffic conditions and incident characteristics. Results show that the proposed mixture model is better than the traditional accelerated failure time model, and it predicts traffic incident duration with reasonable accuracy, as shown by the mean average percent error.

The Research of City Safety Evaluation Method

On the basis of the major hazards of fire and explosion accident model, through the investigation and analysis of several chemical accident, based on existing models of Domino effect, advances in a wide variety of new model of transfer factor synthesis influence level after the accident, on the basis of the fault tree are used to determine the initial event, with software by probability combination method to calculate the impact of the secondary accidents in the area of the largest combination probability of storage tank, and, in turn, calculated based on the combination of the tank farm Domino effect probability. By various initial tank area after the accident the Domino effect probability calculation is not only beneficial to the reasonable layout of the storage tank can also be used for accident emergency decision-making and accident rescue aspects to provide data support [1].

An Evaluation of Energy Absorption under Three-Point Bending Deformation at Higher Deflection Rate for TRIP Steel

In the last few decades, energy absorption of materials becomes an critical issue in a design process of a vehicle because risks of primary and secondary accidents against pedestrians, other road users and structures can be reduced by a performance of absorbing energy in its support structures. Among various materials used for the structures, TRIP steel with favorable mechanical properties such as excellent formability and higher impact energy absorption is attractive to automotive industries. Huge numbers of research works have been carried out to investigate deformation behavior of TRIP steel. However, just few studies can be found on the performance in TRIP steel, especially, at higher deformation rate during the crash of the vehicle. Kinetic energy by higher speed of the vehicle will be consumed by inelastic bending deformation of components. Thus, a consideration of bending deformation at high impact velocity is required for the evaluation of the performance. In this study, the performance in TRIP steel at high deformation rate is clarified by conducting both quasi-static and impact three-point bending tests for pre-cracked specimen.

Emergency Vehicle oriented Traffic Priority Control Strategy at Intersection in Congested Urban Area

Efficient and safe traffic control strategy for emergency vehicle can reduce its travel time and avoid secondary accident. Based on the analysis of its requirement and object, we proposed a novel control strategy at intersection according to the status of emergency vehicle, which can be divided into three parts: “approaching”, “passing “and “recovering”, Furthermore potential safety risk caused by emergency vehicle was also taken into account when making control strategy.From the case study we conclude that with control strategy in this paper delay of emergency vehicle can be sharply decreased by 68.63% with only 19.86% loss of average delay of background traffic. DOI : http://dx.doi.org/10.11591/telkomnika.v12i5.4928

Assessing the risk of secondary crashes on highways

IntroductionThe occurrence of “secondary crashes” is one of the critical yet understudied highway safety issues. Induced by the primary crashes, the occurrence of secondary crashes does not only increase traffic delays but also the risk of inducing additional incidents. Many highway agencies are highly interested in the implementation of safety countermeasures to reduce this type of crashes. However, due to the limited understanding of the key contributing factors, they face a great challenge for determining the most appropriate countermeasures. MethodTo bridge this gap, this study makes important contributions to the existing literature of secondary incidents by developing a novel methodology to assess the risk of having secondary crashes on highways. The proposed methodology consists of two major components, namely: (a) accurate identification of secondary crashes and (b) statistically robust assessment of causal effects of contributing factors. The first component is concerned with the development of an improved identification approach for secondary accidents that relies on the rich traffic information obtained from traffic sensors. The second component of the proposed methodology is aimed at understanding the key mechanisms that are hypothesized to cause secondary crashes through the use of a modified logistic regression model that can efficiently deal with relatively rare events such as secondary incidents. The feasibility and improved performance of using the proposed methodology are tested using real-world crash and traffic flow data. ResultsThe risk of inducing secondary crashes after the occurrence of individual primary crashes under different circumstances is studied by employing the estimated regression model. Marginal effect of each factor on the risk of secondary crashes is also quantified and important contributing factors are highlighted and discussed. Practical applicationsMassive sensor data can be used to support the identification of secondary crashes. The occurrence mechanism of these secondary crashes can be investigate by the proposed model. Understanding the mechanism helps deploy appropriate countermeasures to mitigate or prevent the secondary crashes.

The Hierarchical Risk Source Identification Method Connected with Event Causal Chain in the Emergency Process of Fire Accident of Petroleum Storage and Transportation

The fire accident of petroleum storage and transportation has the characteristics of difficult disposal, wide range of influence, and a long-term hazard. Many derivative accidents or secondary accidents caused in the emergency process show that there are some potential risk sources in the process of accident emergency disposal. Effectively identifying these potential risk sources is the key for the active protective design in advance, and it is a minimum cost mean to prevent and reduce accident harm. In the paper, from the perspective of analyzing the nature of accident’s development and evolution process, the causal relationship between events is studied based on the accident-causing theory. The event causal chain is built in according with the order of event occurrence. The risk sources of accident are mined and identify from the node of event chain, and the hierarchical identification method oriented accident’s risk sources is established. For accident’s risk sources, the possible design measures in advance can be given from the perspective of principle design, structural design and control design. For design measure’s risk sources in emergency process can be mined by using man-human engineering method, and the graded risk sources identification method oriented secondary accidents is established. Combining the two methods, the hierarchical risk source identification method connected with event causal chain is put forward so as to effectively identify these potential risk sources in emergency process. Finally, oil pipeline explosion accident of dalian’s xinggang harbor on July 16, 2010 is taken as a case to verify the feasibility of proposed method.

Endovascular Repair of Traumatic Thoracic Aortic Injury: Final Results From the Relay Endovascular Registry for Thoracic Disease

In blunt thoracic aortic injury, thoracic endovascular aortic repair (TEVAR) offers a less invasive alternative to open chest surgery. New reliable and accurate stent grafts have widened the endovascular treatment options. We report our experience with the Relay stent graft Bolton Medical, Sunrise, FL; Barcelona, Spain) for treatment of this injury. Relay Endovascular Registry for Thoracic Disease (RESTORE) is a multicenter, prospective European registry, which enrolled patients treated with the Relay stent graft for thoracic aortic diseases from April 2005 to January 2009. Regular follow-up examinations were conducted for up to 24 months. This paper analyzes the cohort of patients treated for traumatic aortic injury. Forty adult trauma patients from 12 European centers underwent TEVAR. Mean age was 40 years and 34 patients were male. The proximal landing zone involved aortic arch zones 1 to 2 in 40% and zone 3 in 55% of procedures. Technical success was achieved in all cases. One (2.5%) patient suffered a rupture of the iliac artery. No patient developed procedure-related paraplegia or required conversion to open surgery. Follow-up imaging demonstrated complete exclusion of the traumatic tear and regression of the false aneurysms without endoleak or graft infolding. One late device-related complication was reported; penetration of the distal end of the stent graft treated by stent-graft extension. Thirty-day mortality was 2.5 % (n = 1), and late mortality 2.5% due to a secondary accident. Actuarial 2-year survival was 93.7%. Thoracic endovascular aortic repair with the Relay stent graft is a safe and effective treatment for patients with traumatic aortic injury.

The Operating Efficiency Evaluation of the Highway Network Under Accident Conditions

In order to improve the running safety of highway, to minimize traffic delay, and to avoid the secondary traffic accident, it is essential to evaluate the operating efficiency of the highway network under accident conditions. This article selects the time reliability as evaluation index and compares the index value of the highway network under normal, accident conditions and after emergency traffic organizations. Differences are used to perform an analysis on the impact on traffic of the accident, the result of the emergency traffic organization and the recovery degree of the transport. The paper provides some basis for the traffic organization plan optimization of the road network under the accident conditions.

차량 충돌을 받은 콘크리트 방호벽의 비선형 해석에 관한 연구

도로방호시설의 설계는 차량과 탑승객의 안전뿐만 아니라 안전시설의 손상에 따른 이차 사고 역시 고려하여야 한다. 그러나 지금까지의 연구들은 안전시설의 파괴현상에 대한 연구들은 거의 이루어지지 않고 있다. 본 연구에서는 콘크리트 방호벽에 14ton 트럭 충돌 실험을 실시하고, 비선형 유한요소해석을 실시하여 결과를 분석하고, 콘크리트 강도 및 철망 보강과 같은 상세에 대한 변수해석을 수행하였다. 실험결과 콘크리트 방호벽 상면에 폭 50 cm, 높이 15 cm 정도의 파손이 발생하였으며, 해석에서도 실험결과를 잘 모사하였다. 다른 조건들에 대한 해석결과 콘크리트 강도가 높아질수록 방호벽의 손상 정도가 감소하는 것으로 나타났으며, 철망의 보강 높이는 국부손상에 거의 영향을 미치지 않는 것으로 분석되었다. Design of barrier should be consider the secondary accident caused by a fracture of road safety facilities as well as the safety of vehicles and passengers, but few researches have not conducted on the failure phenomenon of the safety facilities. In this study, the impact test of a 14-ton truck to a concrete barrier was conducted, and then analyzed non-linear behavior of a barrier by FEA. This work also investigates the fracture phenomena of concrete barriers on different detailing such as concrete strength and reinforcement of wire mesh. The collision tests revealed that local fracture with 50 cm in width and 15 cm in height was found in the upper part of a concrete barrier, and the result of analysis was well simulated the test. Also, the interpretations on the different parameters showed that, with respect to concrete strength, the higher the strength of a concrete barrier was, the lower the width of its local fracture and scaling damage was, and that the height of wire-mesh insignificant affected a reduction in local fracture width of a protection wall and its fracture height.

Exploration on Speed-Limit Signs of Traffic Accident Section on Freeways

In order to improve freeways traffic safety, reduce staff and vehicles casualties and prevent secondary traffic accidents, the accident site section on freeway is divided into six regions of the warning zone, the upstream transition zone, the buffer zone, the accident zone, the downstream transition zone and the termination zone. Establish the warning zone speed-limit model by considering the relevant factors of driver's field of vision and transportation distance of visual cognition and then speed-limit programs are proposed according to the warning area speed-limit model. Speed-limit signs of the warning zone take phased settings based on both of those. The results show that the proposed warning area speed limit model conforms to the actual need, decision science, and having important practical value for freeway traffic safety.

Causes and Prevention Measures of Secondary Rear-End Accidents in the Rescue of Highway Traffic Accidents

With increasing number of highway traffic accidents, rescuers are challenged with increasing number of rescue missions, which make rescuers dangerous in the rescue work. In the process of rescue of the highway traffic accidents, secondary rear-end accidents specially lead to the casualties of rescuers and others. There are large number of rescuers who have hurt or even died in secondary rear-end accidents. It is obvious that there is excess tight connection between the cause of traffic accidents and secondary rear-end accidents. Through the research of the highway traffic accidents and their characteristics, we find out the causes of traffic accidents in this paper and then analyze the causes of secondary rear-end accidents in the emergency rescue of highway traffic accidents .By analyzing the causes, we also put forward the practical and effective preventive measures and the management measures at the site. The aim of this paper is to ensure the safety of rescuers, to regulate the program of dealing with the kind of traffic accidents for the traffic accident emergency rescue team and to make suggestions about emergency rescue of traffic accidents in the future. Meanwhile, we hope our suggestions can reduce secondary accidents and resulting life and property losses from the masses and rescuers effectively.

1210 鉄道車両の脱線検知アルゴリズムの開発と防護無線自動発報装置の普及(OS5-1 交通機械の安全,OS5 安全・安心・防災,オーガナイズド・セッション(OS))

1210 鉄道車両の脱線検知アルゴリズムの開発と防護無線自動発報装置の普及(OS5-1 交通機械の安全,OS5 安全・安心・防災,オーガナイズド・セッション(OS))